Removal begins with disconnecting the negative cable from the battery. Next, drain the cooling system. Working in the engine compartment, disconnect the heater hoses and valve where they enter the firewall. Remove the instrument panel and the center console. Remove the heater controls. Label and detach the air ducts, wiring and controls still attached to the heater assembly. Unbolt the heating unit and lift it from the vehicle. Remove the screws and retainers, take out the old heater core and install the new unit. For installation, reassemble the heater unit and check the operation of the air control flaps. If any parts bind, correct the problem before installation. Reinstall the remaining parts in the reverse order of removal. Refill and bleed the cooling system, reconnect the battery and run the engine. Check for leaks and proper system operation.